Reduce cost of cursor invalidation (#15500)

Performance of printing enwik8.txt at the following block sizes:
4KiB (printf): 53MB/s -> 58MB/s
128KiB (cat): 170MB/s -> 235MB/s

This commit is imperfect. Support for more than one rendering
engine was "hacked" into `Renderer` and is not quite correct.
As such, this commit cannot fix cursor invalidation correctly either,
and while some bugs are fixed (engines may see highly inconsistent
TextBuffer and Cursor states), it introduces others (an error in the
first engine may result in the second engine not executing).
Neither of those are good and the underlying issue remains to be fixed.

## Validation Steps Performed
* Seems ok? ✅

src/buffer/out/LineRendition.hpp

@@ -23,21 +23,24 @@ enum class LineRendition : uint8_t
 
 constexpr til::inclusive_rect ScreenToBufferLine(const til::inclusive_rect& line, const LineRendition lineRendition)
 {
-    // Use shift right to quickly divide the Left and Right by 2 for double width lines.
     const auto scale = lineRendition == LineRendition::SingleWidth ? 0 : 1;
     return { line.left >> scale, line.top, line.right >> scale, line.bottom };
 }
 
-constexpr til::point ScreenToBufferLine(const til::point& line, const LineRendition lineRendition)
+constexpr til::point ScreenToBufferLineInclusive(const til::point& line, const LineRendition lineRendition)
 {
-    // Use shift right to quickly divide the Left and Right by 2 for double width lines.
     const auto scale = lineRendition == LineRendition::SingleWidth ? 0 : 1;
     return { line.x >> scale, line.y };
 }
 
+constexpr til::rect BufferToScreenLine(const til::rect& line, const LineRendition lineRendition)
+{
+    const auto scale = lineRendition == LineRendition::SingleWidth ? 0 : 1;
+    return { line.left << scale, line.top, line.right << scale, line.bottom };
+}
+
 constexpr til::inclusive_rect BufferToScreenLine(const til::inclusive_rect& line, const LineRendition lineRendition)
 {
-    // Use shift left to quickly multiply the Left and Right by 2 for double width lines.
     const auto scale = lineRendition == LineRendition::SingleWidth ? 0 : 1;
     return { line.left << scale, line.top, (line.right << scale) + scale, line.bottom };
 }

src/buffer/out/cursor.cpp

@@ -188,11 +188,7 @@ void Cursor::_RedrawCursor() noexcept
 // - <none>
 void Cursor::_RedrawCursorAlways() noexcept
 {
-    try
-    {
-        _parentBuffer.TriggerRedrawCursor(_cPosition);
-    }
-    CATCH_LOG();
+    _parentBuffer.NotifyPaintFrame();
 }
 
 void Cursor::SetPosition(const til::point cPosition) noexcept

src/buffer/out/textBuffer.cpp

@@ -1265,19 +1265,19 @@ Microsoft::Console::Render::Renderer& TextBuffer::GetRenderer() noexcept
     return _renderer;
 }
 
-void TextBuffer::TriggerRedraw(const Viewport& viewport)
+void TextBuffer::NotifyPaintFrame() noexcept
 {
     if (_isActiveBuffer)
     {
-        _renderer.TriggerRedraw(viewport);
+        _renderer.NotifyPaintFrame();
     }
 }
 
-void TextBuffer::TriggerRedrawCursor(const til::point position)
+void TextBuffer::TriggerRedraw(const Viewport& viewport)
 {
     if (_isActiveBuffer)
     {
-        _renderer.TriggerRedrawCursor(&position);
+        _renderer.TriggerRedraw(viewport);
     }
 }
 
@@ -1920,8 +1920,8 @@ std::vector<til::point_span> TextBuffer::GetTextSpans(til::point start, til::poi
         // equivalent buffer offsets, taking line rendition into account.
         if (!bufferCoordinates)
         {
-            higherCoord = ScreenToBufferLine(higherCoord, GetLineRendition(higherCoord.y));
-            lowerCoord = ScreenToBufferLine(lowerCoord, GetLineRendition(lowerCoord.y));
+            higherCoord = ScreenToBufferLineInclusive(higherCoord, GetLineRendition(higherCoord.y));
+            lowerCoord = ScreenToBufferLineInclusive(lowerCoord, GetLineRendition(lowerCoord.y));
         }
 
         til::inclusive_rect asRect = { higherCoord.x, higherCoord.y, lowerCoord.x, lowerCoord.y };
@@ -2032,17 +2032,17 @@ std::tuple<til::CoordType, til::CoordType, bool> TextBuffer::_RowCopyHelper(cons
     if (req.blockSelection)
     {
         const auto lineRendition = row.GetLineRendition();
-        const auto minX = req.bufferCoordinates ? req.minX : ScreenToBufferLine(til::point{ req.minX, iRow }, lineRendition).x;
-        const auto maxX = req.bufferCoordinates ? req.maxX : ScreenToBufferLine(til::point{ req.maxX, iRow }, lineRendition).x;
+        const auto minX = req.bufferCoordinates ? req.minX : ScreenToBufferLineInclusive(til::point{ req.minX, iRow }, lineRendition).x;
+        const auto maxX = req.bufferCoordinates ? req.maxX : ScreenToBufferLineInclusive(til::point{ req.maxX, iRow }, lineRendition).x;
 
         rowBeg = minX;
         rowEnd = maxX + 1; // +1 to get an exclusive end
     }
     else
     {
         const auto lineRendition = row.GetLineRendition();
-        const auto beg = req.bufferCoordinates ? req.beg : ScreenToBufferLine(req.beg, lineRendition);
-        const auto end = req.bufferCoordinates ? req.end : ScreenToBufferLine(req.end, lineRendition);
+        const auto beg = req.bufferCoordinates ? req.beg : ScreenToBufferLineInclusive(req.beg, lineRendition);
+        const auto end = req.bufferCoordinates ? req.end : ScreenToBufferLineInclusive(req.end, lineRendition);
 
         rowBeg = iRow != beg.y ? 0 : beg.x;
         rowEnd = iRow != end.y ? row.GetReadableColumnCount() : end.x + 1; // +1 to get an exclusive end

src/buffer/out/textBuffer.hpp

@@ -169,8 +169,8 @@ class TextBuffer final
 
     Microsoft::Console::Render::Renderer& GetRenderer() noexcept;
 
+    void NotifyPaintFrame() noexcept;
     void TriggerRedraw(const Microsoft::Console::Types::Viewport& viewport);
-    void TriggerRedrawCursor(const til::point position);
     void TriggerRedrawAll();
     void TriggerScroll();
     void TriggerScroll(const til::point delta);

src/cascadia/TerminalControl/ControlCore.cpp

@@ -218,10 +218,8 @@ namespace winrt::Microsoft::Terminal::Control::implementation
     {
         Close();
 
-        if (_renderer)
-        {
-            _renderer->TriggerTeardown();
-        }
+        _renderer.reset();
+        _renderEngine.reset();
     }
 
     void ControlCore::Detach()

src/cascadia/TerminalControl/HwndTerminal.cpp

@@ -248,15 +248,8 @@ try
     // This ensures that teardown is reentrant.
 
     // Shut down the renderer (and therefore the thread) before we implode
-    if (auto localRenderEngine{ std::exchange(_renderEngine, nullptr) })
-    {
-        if (auto localRenderer{ std::exchange(_renderer, nullptr) })
-        {
-            localRenderer->TriggerTeardown();
-            // renderer is destroyed
-        }
-        // renderEngine is destroyed
-    }
+    _renderer.reset();
+    _renderEngine.reset();
 
     if (auto localHwnd{ _hwnd.release() })
     {

src/host/getset.cpp

@@ -730,7 +730,7 @@ void ApiRoutines::GetLargestConsoleWindowSizeImpl(const SCREEN_INFORMATION& cont
             // When evaluating the X offset, we must convert the buffer position to
             // equivalent screen coordinates, taking line rendition into account.
             const auto lineRendition = buffer.GetTextBuffer().GetLineRendition(position.y);
-            const auto screenPosition = BufferToScreenLine({ position.x, position.y, position.x, position.y }, lineRendition);
+            const auto screenPosition = BufferToScreenLine(til::inclusive_rect{ position.x, position.y, position.x, position.y }, lineRendition);
 
             if (currentViewport.left > screenPosition.left)
             {